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Re:Nvidia investigating reports of RTX 4090 power cables bur... by terom on Sunday October 30, 2022 @02:37AM (#33391799)
https://news.ycombinator.com/item?id=33373729 details about the problematic 12VHPWR adapter shipped by nVidia, with extremely questionable engineering (14AWG wires soldered to thin tabs), which should absolutely be recalled as a fire hazard.

I believe it is entirely possible to implement a solid and safe 12VHPWR connector, and its reputation is being destroyed by a shoddy implementation... but that's very much nVidia shooting themselves in the foot.

Re:Nvidia investigating reports of RTX 4090 power cables bur... by echelon on Sunday October 30, 2022 @03:04AM (#33391934)
Maybe they shouldn't have pissed off EVGA?

https://news.ycombinator.com/item?id=32870677

Re:Nvidia investigating reports of RTX 4090 power cables bur... by Kognito on Sunday October 30, 2022 @08:15AM (#33393749)
What does this have to do with EVGA?
Re:Nvidia investigating reports of RTX 4090 power cables bur... by raisin_churn on Sunday October 30, 2022 @08:21AM (#33393793)
Maybe nothing, maybe EVGA, with their reputation for quality and sound engineering, would have looked at the garbage adapter cable Nvidia shipped to board partners and said "Hell no, we're not shipping that to customers" and sounded the alarm on it before thousands of these got into people's homes and offices where they may yet kill someone.

I don't personally like EVGA, had a bad experience trying (and failing) to get warranty replacement for a defective PSU, but I can certainly follow GP's thinking about how EVGA's involvement with this launch might have made a difference.

Re:Nvidia investigating reports of RTX 4090 power cables bur... by echelon on Sunday October 30, 2022 @02:08PM (#33396979)
That was my thinking.

I'm sure Nvidia will get it sorted in time, but they're trying to do a lot right now, and it's noticeably bumpy.

Re:Nvidia investigating reports of RTX 4090 power cables bur... by incrudible on Sunday October 30, 2022 @05:04AM (#33392597)
NVIDIA is a huge company, if they can not manufacture a safe (and durable) 12VHPWR connector, then the PCI SIG design is bad and should be recalled. The design should be such that it would be difficult even for a shoddy manufacturer to create a fire hazard.
Re:Nvidia investigating reports of RTX 4090 power cables bur... by spookie on Sunday October 30, 2022 @05:44AM (#33392825)
Come on now... The parent even included a link detailing it's Nvidia's fault. And that other manufacturers have done a better job.
Re:Nvidia investigating reports of RTX 4090 power cables bur... by stingraycharles on Sunday October 30, 2022 @07:41AM (#33393547)
Exactly, most likely some amount of bureaucracy / subcontractor / cost-cutting yielded this subpar connector.

The linked article gives very good insights in what’s going on.

Re:Nvidia investigating reports of RTX 4090 power cables bur... by incrudible on Sunday October 30, 2022 @09:14AM (#33394217)
I'm not saying it's not NVIDIA's fault, but that the spec has been setting companies up for failure, and it's not just NVIDIA who had these cables fail. Rather NVIDIA is the only company actually shipping these cables at scale into the real world to see the extent of the damage.
Re:Nvidia investigating reports of RTX 4090 power cables bur... by Tsiklon on Sunday October 30, 2022 @06:22AM (#33393075)
There’s power supplies from reputable manufacturers which ship this cable and they do this connector correctly.

Unfortunately NVidia has really screwed the pooch with this as this dangerous adaptor is the first encounter most people will have with the 12VHPWR form factor

Re:Nvidia investigating reports of RTX 4090 power cables bur... by incrudible on Sunday October 30, 2022 @09:05AM (#33394149)
Perhaps so, but these power supplies are few and far between, so we'll have to see about how these actually perform in the long run.

However, you're missing the point. The spec should be designed such that even "non-reputable" manufacturers with sloppier manufacturing methods wouldn't create a fire hazard. These connectors are extra-delicate even though they're supposed to carry higher loads. They will be less robust in practice, for very little gain. That's a poor tradeoff, which makes it poor design.

Re:Nvidia investigating reports of RTX 4090 power cables bur... by Tsiklon on Sunday October 30, 2022 @04:00PM (#33398071)
I am not here to defend Nvidia, nor the quality of the design, I’m not in anyway capable of judging it on it’s technical merits. I think this debacle is a farcical mess.

These new adaptors are included with products Nvidia themselves ship, with themselves as OEM. They know this standard is not common, and they know they need to ship adaptors with them, If they can’t guarantee the quality of it’s manufacturing, then it says there’s possible more worrying things going on behind the scenes.

Re:Nvidia investigating reports of RTX 4090 power cables bur... by tuvan on Sunday October 30, 2022 @07:25AM (#33393456)
600W from a tiny connector is questionable but the issue isn't caused by the 12VHPWR connector. Fault happens on the part that converts 4x older PCIe into the new headers. So this is an adapter issue and not something related to the PCI SIG design. According to Igor's labs investigation what happens is one or two of the welds in the adapter crack and adapter turns into 2x PCIe to 12VHPRW which is not what it's specced out for.
Re:Nvidia investigating reports of RTX 4090 power cables bur... by trashtester on Sunday October 30, 2022 @07:54AM (#33393631)
I think the 50A is a bigger issue than the 600W. Consider that the latest spec for usb-c allows up to 240W in a much smaller cable, but does so at 48V, meaning that the current is only 5A.
Re:Nvidia investigating reports of RTX 4090 power cables bur... by willis936 on Sunday October 30, 2022 @08:20AM (#33393787)
Note that it's in a much smaller cable. Galax tested a 12VHPWR connector at 1530W and the outer jacket stayed under 70C.

https://twitter.com/hms1193/status/1585257428291325958

Re:Nvidia investigating reports of RTX 4090 power cables bur... by lazide on Sunday October 30, 2022 @10:47AM (#33394914)
To be clear - the typical temperature rating you’ll find on mains power cabling in a house is 60c. The highest you’ll typically be able to find is 75c.

70 Celsius is NUTS for that usage, not ‘oh, that’s ok then’

Re:Nvidia investigating reports of RTX 4090 power cables bur... by wongarsu on Sunday October 30, 2022 @11:11AM (#33395114)
It's easier to spec out heat resistive materials for a 5cm cable than for the entirety of a house's mains power cabling. Sure, 70°C is a lot, but I think the point is that it would work if it had to.
Re:Nvidia investigating reports of RTX 4090 power cables bur... by lazide on Sunday October 30, 2022 @11:22AM (#33395208)
It’s a sign of a lot of resistive heat losses and requires specialized insulation and connectors at that level (same for mains). Typically insulation is starting to weaken or even melt at that point.

It’s well outside normal expected operating temperatures for wire.

Re:Nvidia investigating reports of RTX 4090 power cables bur... by willis936 on Sunday October 30, 2022 @12:52PM (#33396097)
Crazy high resistive heating when driven at multiple factors above the rated power isn't cause for alarm though. If you put 50A through your wall outlet you wouldn't be surprised when it got hot. The only application where pulling 1500W through a 12VHPWR connector is even close to possible is when using cryogenic cooling (when the conductive cooling will keep the power cable below ambient despite how many amps are crammed through them).

This data point isn't exhaustive, but it does indicate that the actual safety margin is not as tight as is assumed from this news cycle.

Re:Nvidia investigating reports of RTX 4090 power cables bur... by lazide on Sunday October 30, 2022 @01:43PM (#33396707)
You and I have a very different concept of safe? I don’t think it’s saying what you think it’s saying.
Re:Nvidia investigating reports of RTX 4090 power cables bur... by willis936 on Sunday October 30, 2022 @06:49PM (#33399822)
That is not an issue with the connector though. That is the adapter. That is my entire point. The connector is safe. Shoddy adapters are the problem. Putting multiple supplies in parallel is always very shady, doubly when it's high current through a small piece of metal. That's what's dangerous, not the 12VHPWR connector.
Re:Nvidia investigating reports of RTX 4090 power cables bur... by lazide on Monday October 31, 2022 @12:39AM (#33402146)
That has yet to be shown in the field. We know of one incredibly dodgy adapter, but the issues I’m calling out take time to show up, and lead to issues as well.
Re:Nvidia investigating reports of RTX 4090 power cables bur... by willis936 on Monday October 31, 2022 @12:50AM (#33402195)
Rather than wait for them it's better to do analysis and be predictive.

http://jongerow.com/12VHPWR/

The truth is the plug is more demanding and expensive than lower density options and it's dangerous when corners are cut. This is always true in power electronics, but the risk surface area is higher with a new and demanding connector.

Re:Nvidia investigating reports of RTX 4090 power cables bur... by lazide on Monday October 31, 2022 @12:38PM (#33408350)
I'm not quite sure what your point was in the first sentence - that is always better, yes. We don't have access to analysis done by the EEs in charge of making the plug decisions, but we're already seeing high profile failures, which is unusual.

Even with connectors and cables without those early problems, there are often longer term problems that show up over time - cables fraying at the connectors due to movement, plugs and connectors building up corrosion (and hence having higher resistance), connections loosening or getting bent, etc.

The link you posted, and your later statement seems to support the same view. I'm just repeating it so the folks dismissing this as just an issue with the badly designed adapters Nvidia distributed (in some cases?). It's overall a connector and spec that's on the edge of the performance envelope with some 'obvious' types of field failure modes that don't seem to be properly addressed.

Honestly, I'm a bit shocked they went with 'mountains of parallel power feeds' solution instead of... I don't know, doing 6 gauge stranded, which seems like the obvious choice to me? Parallel power feeds like this are always the source of endless fussing and headaches due to exactly the problems we're seeing. Trying to save a couple cents by using more of the same materials they have on hand I'm guessing?

Re:Nvidia investigating reports of RTX 4090 power cables bur... by incrudible on Sunday October 30, 2022 @08:58AM (#33394092)
The issue is the 12VHPWR connector, not just the adapter.

http://jongerow.com/12VHPWR/

Yes, if "the right materials" are used and the cables are treated "properly" (not bent out of spec, not too many connection cycles) then it's "OK", but those shouldn't be requirements designed into something that cost-conscious consumers are going to be assembling.

Re:Nvidia investigating reports of RTX 4090 power cables bur... by lambdasquirrel on Sunday October 30, 2022 @10:53AM (#33394976)
I think some of the other comments miss an important point. 600W of power draw means that you need 50A of current through those connectors. Or a bunch of transformers. You can design it around the old 12V standard but why? For reference, the amperage leading into the house is typically around 100A; you only need around 24A for an electric range / oven. 50A at 12V is probably not optimal.

Does the old way of building PCIe cards still make sense when the GPU now draws more power than all of the other system components combined? GPU sag (i.e. the card weighs so damn much) is such an issue that one manufacturer actually put a level in their card.[0] The 4090 probably needs three slots just to keep it attached to the motherboard.

When someone buys a desktop these days, it's very often because they need a discrete GPU. You buy a dedicated desktop GPU because the thermal envelope of a laptop can't support a card that would draw 600W - even if it were possible to shrink the card into a laptop (or make the laptop big enough to fit the 600W card). The top of the line Intel processors draw in the neighborhood of 150W but that doesn't necessitate going to a different form factor. Future motherboard and south bridge designs should mount the GPU independently of the other components.

[0] https://www.tomshardware.com/news/geforce-rtx-4090-has-a-spi...

Re:Nvidia investigating reports of RTX 4090 power cables bur... by nordsieck on Sunday October 30, 2022 @11:11AM (#33395107)
> You can design it around the old 12V standard but why? For reference, the amperage leading into the house is typically around 100A; you only need around 24A for an electric range / oven. 50A at 12V is probably not optimal.

In your opinion, if you could force power supply makers to add another voltage rail, which voltage would you pick?

Re:Nvidia investigating reports of RTX 4090 power cables bur... by davrosthedalek on Sunday October 30, 2022 @11:17AM (#33395169)
48V is kinda industry standard, and just below "low voltage" thresholds is most jurisdictions (often 50 or 60V). The cards have switching stages anyway, so it's not that much change (but probably means different power transistors)
Re:Nvidia investigating reports of RTX 4090 power cables bur... by xnyan on Sunday October 30, 2022 @11:59AM (#33395568)
There's not exactly a right choice of voltage per say, it's more of which tradeoffs you are willing to accept. Nothing is free, and higher voltage means more noisy, complex, and expensive SMPS power supplies.

Solving for the problems of higher current, lower voltage DC we use in ATX format supplies today requires higher gauge copper, but the cable run between the GPU and PSU is so shot that the cost of extra copper could very well be less than the increased cost of a higher voltage supply.

Re:Nvidia investigating reports of RTX 4090 power cables bur... by dylan604 on Sunday October 30, 2022 @11:44AM (#33395431)
>For reference, the amperage leading into the house is typically around 100A;

where is this typical? in my experience, typical is 200A service for residential. is mains service amps dependent on provider/region/etc?

Re:Nvidia investigating reports of RTX 4090 power cables bur... by kube-system on Sunday October 30, 2022 @11:50AM (#33395479)
200A is common for newer construction in the US. Many small post-war homes are 100A. It is common to upgrade these homes when it’s time for a new panel.
Re:Nvidia investigating reports of RTX 4090 power cables bur... by dylan604 on Sunday October 30, 2022 @11:55AM (#33395535)
I was under the impression it was the transformers on the pole taking distribution levels down to residential levels that limited this current.
Re:Nvidia investigating reports of RTX 4090 power cables bur... by kube-system on Sunday October 30, 2022 @12:34PM (#33395900)
In the US, generally, the transformer sizing and the line from the pole to your house is the utility company’s problem. When an electrician upgrades a service from 100a to 200a, basically they just ensure the parts between the service line and panel is capable of 200a. —- just the home’s wiring.

Often, those transformers on the pole have some wiggle room in what they can deliver, and just because you upgraded from 100a to 200a service doesn’t mean you’ll actually see a real world change in usage. You usually don’t. Utility companies can over provision that capacity because not everyone on a street switches on their microwave at the same time, etc.

Re:Nvidia investigating reports of RTX 4090 power cables bur... by tomxor on Sunday October 30, 2022 @01:06PM (#33396262)
Maybe we need to start plugging motherboards into GPU cards and have the GPU supply the motherboard with power.